Joint for dental brackets



July 4, 1939. B. A. DICKERSON JOINT FOR DENTAL BRACKETS Filed June 10, 1938 2 Sheets-Sheet 1 F'IG.5

Zhwentor Gttomeg July 4, 1939. B. A. DICKERSON JOINT FOR DENTAL BRACKETS 2 Sheets-Sheet 2 Filed June 10, 1938 Zhwentor attorney i 6 "fl r/"mug Patented July 4, 1939 UNITED STATES PATENT OFFICE JOINT FOR DENTAL BRACKETS poration of Illinois Application June 10, 1938, Serial No. 212,909

7 Claims.

My invention relates to the type of devices described in United States Letters Patent No. 1,854,302. As described in that patent, and as found in practice, the users of such brackets desire the greatest possible amount of radial movement, but it is also vitally necessary that such movements cannot in any way twist the electrical conductors which pass through the brackets for that will, in a very short time, chafe the insulation from the wires or actually break them,

thus causing a short circuit, with attendant disagreeable results.

My invention has for its principal object to provide a bracket, which will permit the greatest l5 movement of the arms enabling the operator to swing his light into a multiplicity of positions.

A further object is while permitting such motion to render it impossible for the electrical conductors to be twisted or broken, thus avoiding all danger of a short circuit.

A further object isto accomplish the foregoing objects in an exceedingly simple and inexpensive manner, thus making it possible for a wider distribution oi these very useful brackets by reason of their lower cost of manufacture.

My means of accomplishing the foregoing objects may be more readily understood by having reference to the accompanying drawings, which are hereunto annexed and are a part of this 30 specification, in which- A Figs. 1 to 5 are more or less diagrammatic views, showing the extent of movement which I have obtained by means of my improved joint;

Fig. 6 is a front elevation of my improvement 35 showing the position of the stops in dotted lines;

Fig. 7 is a vertical sectional view of Fig. 1, some of the partsbeing shown in elevation;

Fig. 8 is a sectional View taken on line 88 of Fig. '7;

. Fig; 9 is a partial sectional view taken on line 9- 9 of Fig. 7; and V Fig. 10 is a sectional View taken on line lllill Similar 'reference numerals refer to similar 45 parts throughout the entire description.

As shown in the drawings, I provide a central joint formed of a cap 1, and a fitting 2. The cap is cylindrical in shape and closed at its top save for a central opening 3, one side of which has a flat 4 to prevent turning of the screwing means, which consists of a screw bolt 5, provided with a head 6, a threaded portion 1 and a tapered portion 8 adjacent threaded portion 7.

u Threaded portion 1 and tapered portion 8 have a flat side 9, coinciding with the fiat 4 in opening 3. The bolt 5. is secured in place by a nut It].

On the lower edge of cap I, is cast or formed a downwardly depending lug II. This lug II is fitted to an annular groove l2, formed in the cyv5 lindrical fitting 2. The groove however, does not run around the cap for a full three hundred and sixty degrees (360), but has a stop l3, formed therein which prevents the arm [4 which is threaded into one side of the cap I, from being 10 swung completely around.

The limit of its movement is clearly shown in Fig. 1.

At the upper end of fitting 2 is a flange l5 which projects and fits into and aligns cap I with fitting 2. The bottom of cap I abuts flange I6 spaced from flange E5 the central portion forming an annular groove i2.

An arm I! extends from the fitting 2 an end cap I 8 which is of cylindrical shape closed at the top with a central opening l9 therein, to receive one end of the stud 20 which secured the end cap l8 to a plug 2!, which closes the lower end of the cap Hi. This plug is provided with a central portion 22, which enters the bottom. of cap l8 and aligns same with plug 2|.

A circumferential flange 23, abuts the end of the wall of cap l8. The flange 23 is spaced from the central portion, forming an annular groove 26, for the reception of a semi-circular projection 25, on the lower end of cap l8.

A stop 24 is placed in the groove 26 to prevent .the projection 25 from swinging through a complete circle. An opening 21 is provided in the central portion 22, to afford a passage for the electric wires (not shown). The stud 20, is provided with a threaded end 28 and a tapered portion 29 adjacent the threaded end. Both the threaded and tapered portion have one side fiatted. similar to bolt 5. A washer 30 having opening 3| with a flat similar to opening 3 and coinciding with the fiat on stud 20 prevents the unscrewing of nut 32 when the cap I8 or plug 2 I is turned.

Any desired extension, light or other article can be secured to the cap 33.

It will be clear from an inspection of Figs. 1 to 5 that I afford a wide variety of positions but that at no time can any arm be swung so as to out oi the wires or even chafe the insulation.

Moreover, I attain my objects with minimum of simple and inexpensive parts which can be assembled by ordinary labor, thus materially reducing the labor charge on the brackets.

I have illustrated a preferred embodiment of my invention, but I do not wish to limit myself thereto as many changes in the details may be made and yet be within the scope of the hereinafter contained claims.

Having described my invention, what I regard as new and desire to secure by Letters Patent is:

1. In an articulated bracket having a plurality of arms adapted to be swung to various positions, a central joint connecting the two arms, said joint comprising a cap for one arm, a fitting for the other, interengaging means on their abutting portions, detachable means to hold said portions in engagement, means to prevent said arms swinging through a complete circle, an end cap mounted on the arm secured to the fitting, said end cap comprising a cylindrical portion having a downwardly depending semi-cylindrical flange thereon, a plug which closes said cap, there being an annular groove on said plug which fits said flange, means in said groove to limit the amount of travel of said flange in said groove, means to hold said flange in said recess and a cap on the outer end of the arm fitted to the central cap.

2. In an articulated bracket having a plurality of arms adapted to be swung to various positions, a central joint connecting the two arms, said joint comprising a cap for one arm, a fitting for the other, interengaging means on their abutting portions, a screw bolt which extends from the fitting to the cap to hold said lug in said groove, means to prevent said arms swinging through a complete circle, an end cap mounted on the arm, secured to the fitting, said end cap comprising a cylindrical portion having a downwardly depending semi-cylindrical flange thereon, a plug which closes said cap, there being an annular groove on said plug which fits said flange means in said groove to limit the amount of travel of said flange in said groove, means to hold said flange in said recess and a cap on the outer-end of the arm fitted to the central cap.

3. In an articulated bracket having a plurality of arms adapted to be swung to various positions, a central joint connecting the two arms, said joint comprising a cap for one arm, a fitting for the other, interengaging means on their abutting portions, detachable means to hold said portions in engagement, a stop in said groove which prevents said arms swinging through a complete circle, an end cap mounted on the arm secured tothe fitting, said end cap comprising a cylindrical portion having a downwardly depending semi-cylindrical flange thereon, a plug which closes said cap, there being an annular groove on saidplug which fits said flange, means in said groove to limit theamount of travel of said flange in said groove, means to hold said flange in said recess and a cap on the outer end of the arm fitted to the central cap.

4. In an articulated bracket having a plurality of arms adapted to be swung to various positions, a central joint connecting the two arms, said joint comprising a cap for one arm, a fitting for the other, interengaging means on their abutting portions, a screw bolt which extends from the fitting to the cap to hold said lug in said groove, a stop in said groove which prevents said arms swinging through a complete circle, an end cap mounted on the arm secured to the fitting, said end cap comprising a cylindrical flange thereon, a plug which closes said cap, there being an annular groove on said plug which fits said flange means in said groove to limit the amount of travel of said flange in said groove, means to hold said flange in said recess and a cap on the outer end of the arm fitted to the central cap.

5. In an articulated bracket having a plurality of arms adapted to be swung to various positions, a central joint formed of a cap cylindrical in shape and closed at its top save for a central opening, the edge of one side of said opening being flat, a screw bolt fitted to said opening, a threaded portion on said bolt and a tapered portion adjacent the threaded portion, a downwardly depending lug on the lower edge of said cap, a lower cylindrical portion having a peripheral groove in which said lug fits, a stop in said groove to prevent the upper cylindrical cap turning 360, a central opening in the end of said second-named cylindrical cap in which said bolt fits, there being threaded apertures in said caps for the reception of the arms of the bracket.

6- In an articulated bracket having a plurality of arms adapted to be swung to various positions, a central joint connecting the two arms, said joint comprising a cap for one arm, a fitting for the other, interengaging means on their abutting portions, detachable means to hold said portions in engagement, means to prevent said arms swinging through a complete circle, an end cap mounted on the arm secured to the fitting, said end cap comprising a cylindrical portion having a downwardly depending semi-cylindrical flange thereon, a plug which closes said cap there being an annular groove on said plug which fits said flange in said groove to limit the amount of travel of said flange in said groove, means to hold said flange in said recess.

'7. In an articulated bracket having a plurality of arms adapted to be swung to various positions, a central joint connecting the two arms, said joint comprising a cap for one arm, a fitting for the other, interengaging means on their abutting portions, detachable taper means to hold said portions in engagement, means to prevent said arms swinging through a complete circle, an end cap mounted on the arm secured to the fitting, said end cap comprising a cylindrical portion having a downwardly depending semi-cylindrical flange thereon, a plug which closes said cap, there being an annular groove on said plug which fits said flange, means in said groove to limit the amount of travel of said flange in said groove, taper means to hold said flange in said recess and a cap on the outer end of the arm fitted to the central cap.

BERT A. DICKERSON. 

